This invention relates to the field of ground fault protective devices sensitive enough to protect humans from the hazards of electric shock resulting from ground fault currents. In the typical alternating current installation, the neutral conductor is grounded at its source. If electrical contact is made with the electrified or "hot" conductor by a person standing on the ground, part of the current is diverted from its normal circuit through the electrified and neutral conductor and follows a ground path circuit through the person back to the neutral grounded at the source. To protect against such hazard, ground fault interrupting devices have been provided for installation in circuit breakers of branch circuits, and in portable units for temporary field use on construction sites. Attempts have also been made to mount such devices in receptacles for installing in ordinary household outlet boxes where ground fault protection is most needed, such as bathrooms, kitchens and garages. By having the entire ground fault sensing and interrupting mechanism in the receptacles where most needed, the entire branch circuit is not interrupted every time the ground fault mechanism interrupts the receptacle circuit.
A disadvantage of the receptacle mounted ground fault interrupting devices hitherto known is their size, usually requiring oversize outlet boxes. The ground fault receptacle in accordance with this invention is compact enough to be installed in the same outlet boxes as conventional receptacles without ground fault protection which the receptacles in accordance with this invention replace. It is not necessary to remove the original outlet boxes and install new ones of larger volume in bathrooms, kitchens and garages in order to obtain ground fault protection wherever desired by using the new receptacles disclosed and described herein.